use internal location where possible
fix thumbnail and links
Merge branch 'master' of https://github.com/GeoNode/geonode into issue-809

Conflicts:
	geonode/layers/models.py
fix the maps thumbnails internal url
Merge pull request #1252 from simod/issue-809

Use OGC_SERVER.LOCATION for internal communication
Updated changelog for version 2.0c2
Pegging the setup.py file to Django 1.5.4.

With 1.6 out Travis is trying to use it
Django 1.5.5 is already out
use public url in the map download page